The Azimuthal $B \to D^{*} \tau^{-} \bar{\nu_\tau}$ Angular Distribution with Tensor Operators

TL;DR

This paper extends the analysis of $B o D^* au u$ decays by including tensor operators, examining their effects on angular distributions and CP violation, and exploring implications for leptoquark models.

Contribution

It introduces a comprehensive calculation of angular distributions with tensor operators, including complex couplings and their impact on observables and new physics models.

Findings

Tensor operators significantly affect azimuthal and CP-violating observables.

Azimuthal observables effectively discriminate between different new physics operators.

Leptoquark models with tensor interactions alter decay predictions.

Abstract

In a recent paper we performed a comprehensive study of the impact of new-physics operators with different Lorentz structures on $\BDstarellnu$ decays, $\ell = e^-, \mu^-, \tau^- $, involving the $b \to c l \nu_\ell$ transition. In this work we extend the previous calculation by including tensor operators. In the case of $\BDstartaunu $, we present the full three angle and $q^2$ angular distribution with tensor new physics operators with complex couplings. The impact of the tensor operators on various observables in the angular distribution, specially the azimuthal observables including the CP violating triple product asymmetries are discussed. It is shown that these azimuthal observables are very useful in discriminating different new physics operators. Finally we consider new physics leptoquark models with tensor interactions and show how the presence of additional scalar operators modify the predictions of the tensor operators.